PDGFRA and gastrointestinal stromal tumor: Additionally, there are no significant differences between KIT and PDGFRA-mutant GISTs in the signaling pathways downstream, revealing that oncogenic signals presented by PDGFRA mutations in GIST are the same as KIT mutations (Heinrich et al., 2003a; Hirota et al., 2003; Corless et al., 2005).